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71.
72.
《Signal Processing: Image Communication》2014,29(4):472-493
We propose a quality-driven cross-layer optimization scheme for wireless direct sequence code division multiple access (DS-CDMA) visual sensor networks (VSNs). The scheme takes into account the fact that different nodes image videos with varying amounts of motion and determines the source coding rate, channel coding rate, and power level for each node under constraints on the available bit rate and power. The objective is to maximize the quality of the video received by the centralized control unit (CCU) from each node. However, since increasing the power level of one node will lead to increased interference with the rest of the nodes, simultaneous maximization of the video qualities of all nodes is not possible. In fact, there are an infinite number of Pareto-optimal solutions. Thus, we propose the use of the Nash bargaining solution (NBS), which pinpoints one of the infinite Pareto-optimal solutions, based on the stipulation that the solution should satisfy four fairness axioms. The NBS results in a mixed-integer optimization problem, which is solved using the particle swarm optimization (PSO) algorithm. The presented experimental results demonstrate the advantages of the NBS compared with alternative optimization criteria. 相似文献
73.
通过客观量测人眼观视时的各项视觉生理指标,并将各项指标嵌入人眼健康舒适度评价模型进行分析运算。经由583人次的人因实验,从视觉健康舒适度、电视屏幕人眼色觉客观量化反馈以及操控可用性3个方面对12款主流品牌的LED电视样机的视觉健康舒适度与人机交互设计进行了测试与评价。 相似文献
74.
75.
供输弹机是武器上易发生故障的子系统,以往的故障检测设备体积庞大。针对这一问题,以某型火炮的供输弹机为对象,结合数据采集的思想,提出了一种基于嵌入式PC104控制总线的便携式故障检测系统。论述了该系统的工作原理,硬件设计,并阐述了基于Visual C++开发工具的系统软件实现。试验表明,该检测系统在保证供输弹机运转的同时,能够快速检测弹丸输送中的多路信号,为准确定位供输弹机的故障,提供了有效的解决方案。 相似文献
76.
在智能视频监视领域,协同利用可见光和热红外传感器,使全天时、精确、鲁棒的智能监视成为可能,具有显著的优势.对可见光-热红外运动目标融合检测的研究进展进行分析和总结.首先,分析了多源传感器融合检测问题,着重说明了融合检测的显著优势、关键步骤及已有公开测试数据集等;然后,详细分析了该类算法的研究进展,从融合策略、运动检测策... 相似文献
77.
《Journal of Visual Communication and Image Representation》2014,25(5):1112-1117
In this paper, a novel multi-instance learning (MIL) algorithm based on multiple-kernels (MK) framework has been proposed for image classification. This newly developed algorithm defines each image as a bag, and the low-level visual features extracted from its segmented regions as instances. This algorithm is started from constructing a “word-space” from instances based on a collection of “visual-words” generated by affinity propagation (AP) clustering method. After calculating the distance between a “visual-word” and the bag (image), a nonlinear mapping mechanism is introduced for registering each bag as a coordinate point in the “word-space”. In this case, the MIL problem is transformed into a standard supervised learning problem, which allows multiple-kernels support vector machine (MKSVM) classifiers to be trained for the image categorization. Compared with many popular MIL algorithms, the proposed method, named as MKSVM-MIL, shows its satisfactorily experimental results on the COREL dataset, which highlights the robustness and effectiveness for image classification applications. 相似文献
78.
《Journal of Visual Communication and Image Representation》2014,25(7):1543-1557
Visual secret sharing, or the so-called visual cryptography, is a well-known scheme that encrypts a secret image into several meaningless share images, usually printed on transparencies, and decrypts as stacking some or all share images by the human visual system. More and more researches about visual secret sharing and its applications have been recently proposed. Unfortunately, the cheating attack in which malicious participants cheat the honest one(s) by forging a fake share image has existed. Since 2006, some cheating prevention schemes have been proposed but suffered from one or more disadvantages as follows: (1) maintaining extra share images used to verify the integrity of a share image prior to stacking, (2) introducing extra pixel expansion, (3) raising heavy computation cost, and (4) giving ambiguous cheating detection. In this paper, a multi-factor cheating–preventing scheme, aiming at exploiting the hybrid codebook to hide the additional verification images into the share images, has been proposed without suffering the above-mentioned deficiencies. Two-factor cheating–detection exploits the design of verification to both share images and stacked results to deter attackers’ cheating. The experimental results demonstrate the proposed scheme is feasible. 相似文献
79.
针对电子设备的测试需求、系统开放性和可扩展的要求,开发了一种基于PXI总线的自动测试系统。详细说明了此系统的硬件构成和软件设计方法。该系统以PXI内嵌主控计算机为核心,以LabVIEW软件为开发环境,并综合运用标准接口和总线技术来实现系统的综合设计。系统具有良好的人机交互界面,在使用过程中运行稳定可靠、测试效率高、使用维护方便。 相似文献
80.
用于控制声纳姿态的水下云台在实际应用中需要实现可视化。将设计云台的Pro/E模型保存为STL标准三维图形文件格式,利用3D Explore软件将该STL文件转换为标准数组。通过Visual C++结合Open GL编程技术,实现了水下云台的可视化,对准确控制云台提供了帮助。 相似文献